Method of attaching caps to containers and of forming hermetic seals



Feb. 14, 192s.

D. M. BOOTHMAN METHOD o ATTAcHIwcAPs To oNTAINERs mm or*l FORMINGH-EmusTIc SEALs Filed` oct. 9. 1924 2 She-ets-Sheet 1 Flfls.

Feb. 14, 1928. 1,659,547

D. M. BooTHMAN METHOD 0F VATTAClIINGr CAPS TO'CONTAINERS AND 0F FORIING.HERIETIG SEALS Filed oct. s.- 19.24v 2 suma-sneer a Flllll.

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UNITED STATES 1,659,547 `PATENT OFFICE.

DALE M. BOOTHMAN, F OAKMONT, PENNSYLVANIA, ASSIGNOR TO ALUMINUM SEALCOMPANY, 0F PITTSBURGH, PENNSYLVANIA, A CORPORATION 0F PENNSYLVANIA.

METHOD 0F ATTACHING CAPS T0 CONTAINERS AND 0F FORMING HERIETIC SEALS.

Application mea october 9, 1924. serial No. 742,555.

In m coendin atent application, Serial Nyo. 5931,)791, t erg isdisclosed a closure seal for containers which comprises a metal caphaving a depending skirt or flange which forms with the outer wall ofthe mouth of a container an annular space in which there is arranged,first a sealing gasket, and below the gasket an annular member whichacts between the container wall and cap liange to retain the cap uponthe container, and in my co-pending patent application Serial No.695,598 there is disclosed a machine for forming closure seals of thecharacter shown in my first mentioned application. In both applicationsthere isa disclosure of a method of forming the various closure sealsshown inthe first application. l

The present invention relates to, and is directed towards the formationof closure seals by the method disclosed in said applications. However,the method for which protection is sought in this application isapplicable to forming seals different than those disclosed in the firstapplication, and is also applicable to the attaching of closure caps tocontainers where no hermetic' seal is effected between the caps andcontainers.

Furthermore, the method herein disclosed 3o maybe practiced by the useof hand tools,

as well as by machines other than that illustrated in the second4application.

An object of this invention is to provide an improved method'of firmlyattaching a cap having a resilient metal flange to a container having arigid open mouth.

A further object is to provide an improved method of not only firmlyattaching a cap having a resilient metal flange to a container having arigid open mouth, but also of simultaneously forming a hermetic sealbetween the capand container.

According to this invention a closure cap having a resilient metalflange is attached to a container having a rigid open mouth by firstapplying the cap to the mouth of the container in such manner that thecap iiange surrounds the outer wall of the container adjacent to itsmouth, and then, while the cap flange is Afree to expand outwardly,wedging an annular retaining member between the container wall and capflange in such a manner that the resilient cap flange is pressedoutwardly and placed under initial tension, by virtue of which tensionthe liange subsequent] the retaining lmemb the container. y

The container may be, and preferably is, a glass jar, bottle, or thelike, which is inherently rigid, but may also be a metal can, pall, orthe like2 having a rigid open mouth. As to the retaining member, it maybe a sealing gasket in the form of a continuous ring or in the form of astring or strip. However, it is preferably a wire.

The container and, cap flange are so formed that when the ca is appliedto the container an annular we ge-shaped space is formed between the capfiange and the outer wall of the container with its wider end adjacentto the outer ed e of the flange. By forming such a wedge-s aped annularspace between the container and iian e, and by so holding the cap uponthe container that the presses inwardly upon er to hold the cap uponflange is free to expand outwardly, the retaining stri may be easilentered into the space and e readily wedyged into position to place theflan e under initial outward tension. The we ge-shaped annular space maybe formed between a container having an outwardly tapering outer walland the flange of the cap extending at ri ht angles to the top of thecap, or'it may e formed between a container having a truly cylin-vdrical outer wall adjacent to its mouth and a cap flange which flaresoutwardly from the top of the cap.

To more securely hold the cap upon the container, the lower ed e of `thecap flange may be crimped rinwar y below the retaining member after thelatter has been wedged into the annular space between the container andflange.

The invention may be further explained and full understood by describingit in greater etail with reference to the accompanying drawin s whichillustrate various types of seals w ich may be formed in the practice ofthe invention, and which also 100 diagrammatically illustrate mechanismwhereby the invention may be practiced. Fig. 1 of the drawings shows acap applied to a container before being attached to it by an annularretaining member; Fig. 2 the container of Fig. l with a retainingmeinber wedged between its outer wall and the cap iiange; Fig. 3 afinished seal of the type illustrated in Fig. 2 with the lower edge ofythe cap crimped inwardly; Figs. 4, 5, 6 and of metal, but which may bevariously constructed providing it hasl a resilient metal ange 2, isshown in Fig. 1 as being applied to the open mouth of glass container 3prior to the wedging in of a cap-retaining membei". In this instance theouter wall of the container tapers outwardly so that an annularwedge-shaped chamber 4 is formed between it and the flange 2 which isperpendicular to the top of the cap. The cap-retaining memberillustrated in Fig. 2 is a ring 5 made of anysuitable-gasket-formingmaterial such as rubber. With the cap applied to the container andsuitably held firmly on it without confining the flange, the retainingring may be wedged between the container and flange by a suitable rolleror other tool 6. The pressure exerted upwardly upon thereta-ining memberis sucient to cause the cap ange' to slightly bulge outwardly, as isillustrated in a somewhat exaggerated manner in Fig. 2. Such outwardpressure upon the flange places it under initial tension so that' theflange subsequently continually presses inwardly upon the retainingmember. As is indicated at 7 in Fig. 3, after the retainingl member hasbeen wedged into position t e lower edge 'of the cap may be crimpedinwardl to prevent outward movement of the retaming member, and hence tomore securely attach the cap to the container.

By so attachino' the cap to a container, the cap is not only rmlysecured in position, but the retaining member serves also to form ahermetic seal between the container and cap.

If desired, a cap may be similarly attached to and sealed upon acontainer by a gasket in the form of a continuous strip. To make such anattachment and seal, preferably two turns of a combined cap-retainingand sealing strip 8 (Fig. lil are wedged between a cap flange 2 l.and te outer wall of a contamer 3. The upper most turn of the gasket servesprimarily as a sealing member 'and the lower turn as a cap-retainingmember. Preferably the outer end of the strip is arranged to ro'ectbelow the lower edge of the flange, as indicated at 9, so that it may bereadily' engaged to remove it from between the container and ange Thismay be done by merely pulling downwardlynpon the end 9 of the stri Whilee cap-retaining member may be a gasket in the Vform of a ring or astring as as been explained, it preferably consists of a wire wedgedbetween the container and cap ange in the manner described. The wire maybe of any suitable metal, but is preferably aluminum. In Fig. 5 there isillustrated a container 3b having a cap 1b attached to 1t by slightlymore than a single turn of a wire 10 wedged between the container andlwire 10, and a hermetic seal is formed bel tween the cap and containerby a gasket ring 5 similar to that illustrated in and explained withreference tov Figs. 2 and 3. In forming this seal, the gasket ring 5 isirst wedged between the container and cap iiange and thereafter the capretaining wire 10 `is wedged into the posit-ion indicated.

Thepreferred form of seal made according to this invention is thatillustrated lin v lFig. 7 in which a hermetic seal is formed between acontainer 3 and a cap 1 by a stringlike gasket 8, and in which the capis at tached to the container by a strip of wire 10. As indicated, theouter end 12 of the sealing gasket 8 is preferably arranged belowl theinner end 13 of the wire 10, so that when the wire is removed byengaging and pulling downwardly upon its outer exposed end 9, the innerend 13 of the wire will cause the outer end 12 of the gasket to beexposed below the cap iange so that it in turn may thereafter be engagedand removed. The manner of forming this particular seal will presentlybe explainedv with reference to mechanism diagrammatically illustratedin Figs. 10, 11 and 12.

It has been previously explained that it is desirable to vso shape thecap and the outer wall ofthe container that there is an annularwedge-shaped space between the flange and container when the cap isapplied to it. In the forms of seals thus far explained such` an annularSpace is effected by providing a container having an outwardly taperingouter wall and a cap having a `iiange which is perpendicular, orsubstantially so, to its top. In the structure shown in Fig. 9, awedge-shaped annular space 15 is formed between a truly cylindricalouter wall of the top of a bottle 16 and a flange 2 which lia-resoutwardly from the top of a cap. The cap in this instance is attached tothe container by a retaining wire 10, but

may be attached by any of the other forms of retaining memberscontemplated herein.

To properly center the cap on a containerwhen the two are assembledprior to the4 of a suitable cork 17.

In the various forms of seals thus far illustrated the rigidity of themouths of-the containers is inherent in the material of which they areformed.` However, the invention is applicable to attaching closure capsto containers which of themselves are' not inherently rigid, providing.the mouths of the containers are suitably rendered rigid so that, whenthe cap-retaining member is wedged between them and the flanges of thecap applied to them, the flanges will be placed under initial outwardtension. In Fig. 8 there is illustrated a container 3 formed of sheetmetal, the mouth of which is made rigid by so shaping it as to form anannular bead 18. A cap 1f may be attachedto such a container by means ofa gasket ring 5f or by any of the forms of seals illustrated in theother figures, and which have previously been explained.

In Figs. 10, 11 and 12 there is somewhat* diagrammatically illustratedmechanism for attaching a cap to a container which may be used to formaccording to this invention the various seals which. are hereinillustrated and which have been described, but which is particularlysuitable for forming the seal illustrated in Fig. 7. These views showsuccessive steps in the cap-attaching and sealing operation. Themechanism which is the same as that illustrated in my said applicationSerial No. 695,598, includes a rotatable support 18 for the container 3"and a rotatable head 19 for holdinga cap ld applied to the mouth of thecontainer. Project-ing upwardly between the cap flange and the outerwall of the container there 1s a roller 20 (Fig. 10) for wedging betweenthe flange and container the string-like gasket 8l which is adapted tobe fed to the roller through ya tube 21. After the holder 18 and head 19have made slightly more than aV complete revolution, the' inner end ofthe retaining wire 10dl is fed through a' tube 22 (Fig. 11) and upon asecond4 roller 23 which wedges the wire against the gasket, which inlturn is further wedged into sealing position. After the support 18 andhead 19 have made somewhat more than a second complete revolution, theyare simultaneously moved upwardly with relation to the wedging rollers20 and 23, as indicated in F 12, so that the outer end 9d of the retammgwire may extend below the lower The characterizing feat-ure of the im-vproved method of attachin a cap to a container is that the resilientange of the cap is pressed outwardly by wedging between it and a'container havin a -ngid open mouth a cap retaining mem er which placesthe flange under initial tension. By virtue of such` tension the flangecontinuously presses inwardly upon the retaining member to hold the capupon the container. In addition to this, the method contemplates in itsmore specific aspects the simultaneous forming of a hermetic sealbetween the ca and container, the seal preferably being e fected bywedging a strip of gasket between the container and cap flange, and theattachment of the cap to the container by thereafter wedging a wirebetween the cap and container back of the sealing strip.

According to the provisions of the atent statute, I have described theprincip e and manner of practicing the invention with flange surroundingthe outer wall of the. con-` tainer adjacent to its mouth, said flangebeing free to expand outwardly, and then` pressing the flange outwardlyb wedging a cap retaining member between t e cap flange and the outerwall of the container, thereby placing the flange vunder initial tensionby virtue of which it subsequently presses inwardly upon the retainingmember.

2. The method of attaching acap to a container having a rigid openmouth, which comprises first applying to the mouth of the container acap havmg a resilient metal flange surrounding the outer wall of thecontainer adjacent to its mouth, said flange pressing 'the Bangeoutwardly byvwedging a cap retaining wire between the cap Bange and theouter wall of the container, thereby placing the Bange under tension byvirtue of which it subsequently presses inwardly upon the wire to holdthe cap firmly attached to the container.

3. The method of attaching a cap to a container having a rigid openmouth, which comprises first applying to the mouth of the containera caphaving a resilient metal Bange surrounding the outer Wall of thecontainer adjacent to its mouth, said Bange being free to expandoutwardly, then pressing the flange outwardly by wedging a cap retainingmember between the cap Bange and the outer .wall of the container andabove the outer edge of lthe Bange, thereby placing the Bange underinitial tension, and linally a crimping inwardly the outer edge of: theBange below the cap retaining member.

4. The method of attaching a cap to a container having a rigid openmouth, which comprises applying to the mouth of the container a caphaving a resilient metal Bange surrounding the outer wall of thecontainer adjacent to its mouth and forming with such wall awedge-shaped annular space, said Bange being free to extend outwardly,and then pressing the Bange outwardly by wedging a cap retaining memberin said space and between the container and cap Bange, thereby placingthe Bange under initial tension by virtue of which it subsequentlypresses inwardly upon the cap retaining member.

5. The method of hermetically sealing a container and attaching a cap toit, which comprises applying-to a container having a rigid open mouth acap having a resilient metal Bange so that the Bange surrounds the outerwall of the container adjacent to its mouth, said Bange being free toexpand outwardly, and then pressing the Bange outwardly by wedging asealing gasket between the container wall and cap Bange, whereby Yahermetic sealvis formed between the cap and container and theBange isplaced under initial tension, by virtue of which tension the cap Bangesubsequently presses inwardly upon the gasket. n 6. The method ofsealing a container and attaching a cap to it, which comprises firstapplying to a container having a rigid mouth a cap having an unconfnedresilient metal Bange surrounding the outer wall of the containeradjacent to its mouth, and then wedgin between the container and capBange st a sealing gasket and thenl back of the gasket .a cap-retainingstrip, whereby the Bange is pressed outwardly and placed under initialtension by virtue of which it subsequently presses inwardly upon thegasket and strip to tighten the seal and hold the cap upon thecontainer.

7. The method of sealing a container, which comprises Brst applying to acontainer having a rigid mouth a cap having an uncontined resilientmetal Bange surrounding the outer wall of the container adjacent to itsmouth, and then wedging between the container and cap Bange Brst a'sealing gasket and then back of the gasket a capretaining vstrip of wirewhereby the Bange is pressed outwardly and placed under initial tensionby virtue of which it subsequently presses inwardly upon the gasket andwire to tighten the seal and hold the cap upon the container. Y

8. The method of hermetically sealing a container and attaching a cap toit, which comprises applying to a container having a rigid open mouth acap having an uncon- Bned resilient metal Bange surrounding the outerwall of the container adjacent to its mouth and forming with such wall awedgeshaped annular space, and wedging in said DALE M. BOOTHMAN.

